A Canadian woman who tried to smuggle her cat into New Zealand in a handbag has been caught and put on a flight back home.

The woman's ploy to get her four-year-old cat Bella into the country was only discovered when border agents at the arrivals terminal in Auckland got suspicious about her and her husband's muddy boots.

The couple - both in their 20s - were picked out for an inspection and the woman was "very reluctant" to have her handbag examined by an X-ray machine, officials said.

It was then that the authorities found the "very docile" cat, who they suspect may have been drugged to keep her quiet for the 7,000-mile trip.

The woman claimed she had told a ticketing agent about Bella when she bought her ticket.

Craig Hughes, from the Ministry for Primary Industries, said he doubted if the woman's story was true - and even if it was, it was still unacceptable to bring a cat across the border without declaring it.

He said the woman's actions were "dangerous" because foreign cats could introduce non-native ticks and diseases into the country.

New Zealand has strict regulations for importing pets with cats and dogs from most approved countries needing an implanted microchip, and they have to be kept in quarantine for a minimum of 10 days.

He said the woman was upset about being refused entry to New Zealand and she, along with her cat, were sent back home.

"She had plans to have a nice holiday with her husband in New Zealand," he said. "And her cat."